The Siemens 3RA2711-1CA00 is a SIRIUS function module that adds IO-Link communication and star-delta (wye-delta) starting logic to a compatible contactor. It is not a standalone starter — it snaps onto the front of a communication-capable 3RT20…-…..-0CC0 contactor in frame sizes S00, S0, S2, or S3. The module handles the control sequencing for star-delta motor starting, so the contactor itself only needs to switch the main power. Control supply is 24 V DC, which is standard for modern PLC-based panels. The module includes a built-in varistor for surge suppression on the control circuit, saving a separate suppressor component on the DIN rail.
Wiring and connections
Screw-type terminals on a removable block accept 1x 0.5–4 mm² or 2x 0.5–2.5 mm² solid/stranded, and with ferrules 1x 0.5–2.5 mm² or 2x 0.5–1.5 mm². AWG for auxiliary contacts is 2x 20–14. The removable terminal block is handy for pre-wiring the module on the bench before snapping it onto the contactor.
Installation altitude up to 2000 m above sea level without derating. Withstands 11 g / 15 ms shock and 10–55 Hz / 0.35 mm vibration.
EMC and electrical ratings
EMC immunity meets IEC 60947-1 environment A (industrial sector). Emitted interference complies with CISPR 11, environment A. Electrostatic discharge immunity is 8 kV per IEC 61000-4-2.